[PATCH] qemu-iotests: restrict 264 to qcow2 only

[Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>]

264 is unprepared to run with different formats, for example luks needs
handling keys, cloop doesn't support image creation, vpc creates image
larger than requested (which breaks "Backup completed: 5242880" in test
output).

The test is here to check nbd-reconnect feature and we actually don't
need it for all formats. Let's restrict it to qcow2 only.

Reported-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 tests/qemu-iotests/264 | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tests/qemu-iotests/264 b/tests/qemu-iotests/264
index c8cd97ae2b..131366422b 100755
--- a/tests/qemu-iotests/264
+++ b/tests/qemu-iotests/264
@@ -24,6 +24,8 @@ import iotests
 from iotests import qemu_img_create, qemu_io_silent_check, file_path, \
         qemu_nbd_popen, log
 
+iotests.verify_image_format(supported_fmts=['qcow2'])
+
 disk_a, disk_b, nbd_sock = file_path('disk_a', 'disk_b', 'nbd-sock')
 nbd_uri = 'nbd+unix:///?socket=' + nbd_sock
 size = 5 * 1024 * 1024
-- 
2.21.0